[reefmutt]

I’m kind of leaning towards the vermitid snails. You are doing everything else right.
Their digestive web is really irritating to sps. And if you are totally infested, maybe the webs are too much for the corals or maybe there is enough of the web and its chemicals in the water that the sps just don’t or can’t tolerate it..
I have heard that either KZ coral snow or Aqua Forest Build will kill off thenvermitod snails because the chalky substance in those products gets trapped in the web and the worms
Can’t proces it properly and they die off..
Not a super expensive experiment...
but really, I go very seriously out of my way to keep those snails out of my system, they are no good.